Start with where and when
A bathroom-only problem differs from whole-house winter condensation.
Check user-accessible controls and filters only as directed
Manufacturer-labelled user maintenance can be recorded before service.
Do not block or alter unknown ventilation paths
Changes can affect pressure relationships and combustion appliances.
A retrofit should be designed as a system
Air sealing and insulation can change ventilation needs.
Safety boundary. General planning information only. Do not open, dismantle or work on hazardous electrical, gas, structural, fire-protection or contaminated-water systems unless you are appropriately qualified and authorized.